Device for preventing back-firing in explosive-engines.



No. 825,835. PATENTED JULY 10, 1906.

' G. HOLLOWAY. DEVICE FOR PREVENTING BACK FIRING IN EXPLOSIVE ENGINES.

APPLICATION FILED MAR-13. 1905.

WITNESSES: 5% pW/M.

Altorneyg.

INVENTOR v UNITED ST ATES FATE N T OFFICE.

GEORGE HOLLO\VAY, OF CLYDE, OHIO, ASSlGNOR TO ELMORE MANU FACTURING COMPANY OF CLYDE, OHIO.

DEVICE FOR PREVENTING BACK-FIRING IN EXPLOSlVE-ENGINES.

Specification of Letters Patent.

Patented July 10, 1906.

Application filed March 13, 1.905- Serial No. 249,797.

To (til whom-it nm l concern.-

Be it known that I, GEORGE HOLLOWAY, of Clyde, in the county of Sandusky and State of Oliio,,have invented certain new and useful Improvements in Devices for Preventing Back-Firing in Ex losive-Engines; and'I hereby declare that t 1e following is a full, clear, and; exact description thereof, reference being had to the accompanying drawings, which form part of this specification.

This invention is an improvement in what are comm'only termed gas-engines operated by the explosive force of gases or carbureted air, and has especial reference to the type of engines in which the explosive mixture is first compressed and then admitted into the working or exploding chamber in the cylinder and ignited, the compression occurring in th e pump-chamber, which is ordinarily the crank-chamber of the engine. In this class of engines it is necessary to provide means to prevent back-firing or explosion of the mixture in the compression-chamber by reason of premature ignition of the gases in the by-pass and Working chamber before the ports connecting the com ression-chamber and the exploding cham er or cylinder proper are closed. Such back-firing or explosions in the by-pass and compressionchamber causes erratic running of the engine, blowin gout the charge from the pump-chamber into the carbureter, and other annoyances. Various attempts have been heretofore made to preventthis back-firing; and the'pr esent invention consists in a novel and improved device for that purpose, comprising a screen of peculiar. construction placed in the by-pass or passage between the compression and working chambers and by which even if premature ignition occurs in the working chamber the gaseous mixture in the compression-chamber will not be fired.

The invention therefore consists in the novel construction and arrangement of this screen, as hereinafter claimed, and said screen is illustrated in the accompanyin drawin s and hereinafter described in detai with re erence thereto.

In said drawings, Figure l is a longitudinal sectional elevation of a gas-engine equipped with my invention far preventing back-firing. Fig. 2 is an eniargedfdetail section on line'2 2, Fig. 1. Fig. 3 is aplan view of the screen detached.

The engine comprises a cylinder A, con nected to or formed with a crank-case B, in which the crank C of the main shaft is inclosed air-ti htly. A piston D works in the cylinder an case, so as to serve both as the engine and pump-piston, and is comiected directly with the crank by a rod E. The chamber 1 in the cylinder is the working chamber and the chamber 2 in the crank-case is the pump or compression chamber.

Explosive gases or mixtures thereof are admitted into chamber 2 throu'gh port 2, which may be connected to any suitable carbureter or gas-supply. This port 2' is closed by the piston just after it begins its inward or working stroke. Chamber 2 also communicates by a port 2 with a by-pass or passage 3, which is preferably a rectangular recess in the wall of the cylinder and casing, not marring their symmetry and which is covered by a removable plate 3 and communicates throu h a port 1 with the Working chamber 1. Then the piston is at the end of its working stroke, the burned gases escape from the chamber 1 through orts 1 The piston in the example shown orms the main valve of the engine and controls the ports 1, 1 and 2.

It is necessary to provide means to prevent the fresh gases in the bypass 3 and chamber 2 being ignited when the port 1' is opened by the heat of the walls of c amber 1 or by any burning, partly unconsumed gases remaining therein. For this purpose I lace a baffle or screen F in the byass, whic screen preferably consists of a ayer f of finely woven or reticulated metal and one or more layers of coarsely perforated or reticulated metal.

Preferably the screenis composed of one layer f of finely-woven brass or refractory wire inclosed between two layers f f 2 of perforated sheet metal, all bound together by rivets f. The screen is arranged within and diagonally across the by-pass 3, and said screen extends from port 2 to a point above the port 1, being closely fitted within the by-pass at its edges, so that there will be no chance of flame passing around the screen.

The screen is placed in a diagonal position to secure the greatest amount of space possi- 5 ble in the assage-way on account of the liability .of t e screen to become clogged by burned oil or a formation of carbon or other substances in the small perforations of the screen, it the screen were placed in a vertical position itsarea would be .s'o small that I it would soon choke, so that it must he s. great deal larger than the ports or the passage-way 3 screen and the'sides of the hyass. .The-

screen isproperly positioned in t e by-pass. b meansof projections F on the rear ends o the fiangesF, which position its rear edge relative to port 2", and its front end may-be upheld over port 1.. by means of pins E as shown, or in other suitable manner. Preferably part of one-layer f direotly'over the port 1?" is imperforate, as shown at f, so that if flame should s urt into the lay-pass through port 1"- it won .d strike the imperioratepart f rather than the fine layer. struction the finer part of the screen is stifiened and protected by the coarser layers, and

the durability of the screen is indefinitely prolonged as compared with the life of a single fine screen.

The coarsely-perforated layer f ibreaksand disseminates any flame which might enterthe bypass-before it contacts withthefine layer, and the strands of the fine-layer must practically beburned entirely away before back-firing could occur. I consider the layer f (adjacent port 1) more important than the layer f (adj acent port 2,) and although the construction and arrangement shown 1n -anti-back-firing device, arranged in the gasdrawings is preferred I do not wish to be restricted to this articular construction, as-it may be modified. within. the scope of my invention, and the formv of the screen would necessarily be varied according to the dimensions and arrangement of the by-pass and ports.

. While, as above stated, Iprefer tic make the fine layer f of reticulated" or woven-wire mesh and the outer layers f f 2 of coarselyperiiorated. sheet metal, I do not intend to restrict myselfin .the claims to. either reticulated. or woven or perforated layers, reticulated-i 'or woven wire and. perforated sheets being well-known equivalents.

. In theengine shown the c cle ofoperations is.as follows: A charge 0 explosive gases having ignit the piston D is driven forward and inso. doing; compresses the explosive mixture previously admitted into chamber '2. As the iii-1101).. nears the; end ofi its, inward 'stroke it. uncovers. port 1',. allowing the burned gaseato-exhaust. Then it uncovers port 1, whereupon the compressed gases in chamber 2 rushthrough; port 2* intoby-pass 3 and through. the screen. F and port 1 into the working chamber, driving out the burned gases.- Then aethe'piston moves back it closes p'orts 1 and 1 andcompresses the fresh explosive gases until it has completed By this con-.

boen'admitted intofchamber 1 and.

chamber 2 to be compressed on the next power stroke of the pistoncaused by the ignition'of the ases in chamber 1.

Having t us described my invention, what I claim as new, and desire to secure by Lettors Patent, is' I I In combination, a gas-engin having a working chamber, and a pump-c amber in axial alinement, inlet and outlet ports to said chambers, a common piston working in and between said chambers and controlling said ports, and a by-passconnecting the'pumpchamber with the inlet-port of the working chamber; with a baflle or screen in said bypass having an imperforate portion directly over or opposite the inlet-port of the working chamber, substantially as described.

2. In combination with a gasengine, anaDti-back-firingdevice, arranged in the gasinlet passage to the working chamber, and

consisting of a finely-perforated metal layer, and coarsely-perforated layers inclosi'ng the finelyerforated layer, said device having an imperf .the inlet-port of the Working chamber.

3'. The hereindescribed. device for pre-- venting back-firing in gas'-engines,-cdnsisting of a screen having its sides upturned, and provided with projections at one end, and an imperforate portion near its other end, substantially as set forth.

4. In combination with ages-engine, an

inlet passageto the working; chamber, and consisting of afinelyerforated metal sheet,

7 and layers of coarse y-peiiforated metal inorate portion directly over or opposite closing thefinely-perforated sheet, andnaid device. having an imperforato portion. directly over or opposite the i'nlet-port of the working chamber. 4.

- 5." In-combi-nation, ages-engine having-a working chamber; and a. pump-chamber in axial alinementjinlet and outlet ports to-said chambers, a common: pistonworkin in: and between said chambers and control 'ng said.

IIO

ports and a by-pass'connecting the-pump chamber with the inlet-port of, the working chamber; with abaflie orscreenin said by-- pass; formed of a. centralllayer'of.finely-perforated metal, and incl'osing layers of coarse perforated metal, andihaving an. imperfoi ate portion directly over on 0 p'osite the in'l'cts I Pm the-Working than or, substantially s-described. i 1

6;. In combination with a. gas'rengine hifliV ing a working chamber, apumpwhamber, a; piston adapted to compness explosive mixturesin thepump-chamber, and a by -pass for admitting explosive mixtures from: thepump-chamber to the working chamber; a

screen arranged within the by-pass and closmg communication betweentheworking and pump chambers except through its mosh, said to the working chamber,

screen having an imperforate portion opposite the inlet to the working chamber, substantially as described.

7. In combination, an explosive-engine having a working chamber, a compressionchamber, and a by-pass between said chambers; with a screen in said by-pass having its sides upturned and closely fitting the sides of the by-p ass for the purpose and substantially as described.

8. In combination, an explosive-engine, having a working chamber, a compressionchamber and a bypass connecting saidchambers; with a screen in sazidby-pass having an imperforate portion directly opposite the inlet for the purpose and substantially as described.

9. In combination, an explosive-engine having a working chamber, a compressionchamber, and a by-pass leadin from the compression-chamber to the wor g chamber; with an anti-back-firing screen arranged in the by-pass and ,having its sides upturned compression-chamber to the wor and closely fitting the sides ofthe by-pa'ss to' prevent the passage of gas around the edges of the screen, and provided With'projections at one end for the purpose and substantially as described.

'10. In combination, an explosive-engine having a working chamber, a compressionchamber, and a by-pass leadin from the g chamber; with a device for preventing back-firing comprisin a screen having its si es upturne and provi ed with projections at one end and an imperforate portion op osite the inletto the Working chamber, sub scribed.

In testimony that I claim the foregoing as my own I afiix. my signature in presence of two Witnesses.

GEORGE HOLLOWAY.

In presence Of J. O. CRAIG, HOMER METZGAR;

stantially as d'e-' 

